Energy storage caddy for a welding system

ABSTRACT

Embodiments of energy storage caddies adapted to couple to a welding power supply are provided. The energy storage caddies may include an energy storage device, a charger, control circuitry, and power conversion circuitry. Certain control circuitry may be adapted to control the energy storage device to discharge to provide a direct current (DC) voltage output to the welding power supply when a weld load demand is detected, to monitor a charge level of the energy storage device, and to alert a user to an error when the charge level of the energy storage device falls below a predetermined limit.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Non-Provisional Patent Application of U.S.Provisional Patent Application No. 61/261,958 entitled “Battery Pack”,filed Nov. 17, 2009, which is herein incorporated by reference.

BACKGROUND

The invention relates generally to welding systems and, moreparticularly, to primary power supplies for welding power sources.

Welding is a process that has become increasingly ubiquitous in variousindustries and applications. As such, a variety of welding applications,such as in construction and shipbuilding, may require welding devicesthat are portable and can easily be transported to a remote weldinglocation. Accordingly, it is often desirable for such welding devices tobe operable as standalone units remote from a power grid or otherstationary primary power source. Unfortunately, to replace a traditionalwelder with a hybrid system may present a high monetary cost.Furthermore, the incorporation of alternate power sources into thewelder may add to the bulkiness of the overall package, thus decreasingportability. Accordingly, there exists a need for improved weldingsystems that overcome such drawbacks.

BRIEF DESCRIPTION

In an exemplary embodiment, a welding system includes a welding powersupply adapted to provide a power output for a welding operation. Thewelding system also includes an energy storage caddy. The energy storagecaddy includes at least one energy storage device, is adapted to coupleto the welding power supply, and is adapted to provide a direct current(DC) voltage output to the welding power supply. The welding powersupply is adapted to receive the DC voltage output and to convert the DCvoltage output to the power output for the welding operation.

In another embodiment, a retrofit kit for a welding system includes anenergy storage caddy adapted to generate a power output and to providethe generated power output to a welding power supply. The energy storagecaddy includes an energy storage device adapted to discharge to producethe power output and control circuitry coupled to the energy storagedevice and adapted to regulate the power output based on a charge levelof the energy storage device, a load demand at the welding power supply,and a temperature of the energy storage device.

In another embodiment, an energy storage caddy for a welding systemincludes an energy storage device and control circuitry adapted tocontrol the energy storage device to discharge to provide a directcurrent (DC) voltage output to a welding power supply when a weld loaddemand is detected, to monitor a charge level of the energy storagedevice, and to alert a user to an error when the charge level of theenergy storage device falls below a predetermined limit.

DRAWINGS

These and other features, aspects, and advantages of the presentinvention will become better understood when the following detaileddescription is read with reference to the accompanying drawings in whichlike characters represent like parts throughout the drawings, wherein:

FIG. 1 illustrates an exemplary welding system including a welder and anenergy storage caddy in accordance with aspects of the presentinvention;

FIG. 2 is a block diagram illustrating exemplary components of theenergy storage caddy of FIG. 1 in accordance with aspects of the presentinvention;

FIG. 3 is a block diagram illustrating an exemplary charging system inaccordance with aspects of the present invention; and

FIG. 4 is a block diagram illustrating exemplary control logic that maybe employed by control circuitry that may be disposed in the energystorage caddy of FIG. 1 in accordance with aspects of the presentinvention.

DETAILED DESCRIPTION

As described in detail below, embodiments of an energy storage caddyadapted to retrofit existing welding power supplies is provided. Theenergy storage caddy is adapted to provide primary power to a weldingpower supply, which may include power conversion circuitry configured toconvert the received power to an appropriate weld power output. To thatend, the energy storage caddy may include one or more energy storagedevices, such as batteries, fuel cells, and so forth, capable ofproviding power (e.g., by discharging) without the need for any externalconnections. That is, the energy storage caddy is capable of operatingas a standalone unit during operational periods. Furthermore, the energystorage caddy may be capable of recharging the one or more energystorage devices disposed therein, for example, via coupling to anexternal or internal charger and primary power supply.

Turning now to the drawings, FIG. 1 is a perspective view of anexemplary welding system 10 in accordance with aspects of the presentinvention. The illustrated welding system 10 includes a welding powersupply 12 with a front panel 14, a back panel 16, and a control panel 18disposed in the front panel 14. As shown, the front panel 14 is adaptedto receive a welding torch and a ground clamp, which extend to a weldlocation. The system 10 further includes an energy storage caddy 20adapted to be coupled to the welding power supply, for example, via areceptacle disposed in back panel 16, as indicated by arrow 22. As such,the system 10 may be capable of generating and providing power for awelding operation as a standalone unit without coupling to an additionalprimary power source (e.g., a power grid or generator). In theillustrated embodiment, the welding system 10 further includes primarypower 21 that may also supply the welding power source with power, forexample, when the welding operation occurs in close proximity to theprimary power source, as indicated by arrow 23.

It should be noted that the energy storage caddy 20 may be capable ofretrofitting existing welding power supplies that typically require aconnection to a primary power source. As such, the energy storage caddymay be capable of providing portability to power supplies that weredesigned for use in close proximity to a primary power source, such aspower from a wall plug. For example, the energy storage caddy 20 may becapable of providing a DC voltage output between approximately 80V and500V to power existing welding, cutting, and heating power supplies. Forfurther example, some embodiments of the energy storage caddy 20 may becapable of providing a DC output between approximately 110V and 300V. Assuch, embodiments of the energy storage caddy are adapted to allow thewelding power supply to operate for a predetermined period of time(e.g., as long as the energy storage device has sufficient charge) whenother AC power is not available or is inconvenient. Furthermore, in someembodiments, more than one energy storage caddy 20 may be utilized tosupply the welder 12 with power throughout a welding operation. Forexample, when located remote from an alternate primary power source,multiple energy storage caddies may be utilized in series or in parallelto provide the necessary power for a welding operation.

During operation, the energy storage caddy 20 is adapted to provide apower output to the welding power supply 10. To that end, the energystorage caddy 20 may include one or more of the exemplary componentsillustrated in the block diagram of FIG. 2. The illustrated energystorage caddy 20 includes a controller 24, an energy storage unit 26, acharger 28, and power conversion circuitry 30. The controller 24includes control circuitry 32 and memory 34. The energy storage unitincludes an energy storage device 36 and an optional additional energystorage device 36′, although any number of energy storage devices may beincluded in further embodiments. As shown the energy storage caddy 20 isconfigured to provide a power output 38 that is routed to the welder andan auxiliary power output 40, although in other embodiments, the caddy20 may not provide the auxiliary output 40.

The energy storage unit 26 is adapted to generate and provide a poweroutput suitable for use by a welder. For example, the power output maybe a DC voltage output within a range accepted by current welding powersupplies. To that end, the energy storage unit 26 includes energystorage devices 36 and 36′. The energy storage devices may be Li ionbatteries, Ni-Mh batteries, Ni—Cd batteries, fuel cells, a combinationthereof, or any other suitable standalone power generator. In oneembodiment, the energy storage device 36 is a battery configured todischarge to produce the power output 38. Still further, in someembodiments, the outputs of one or more energy storage devices may becoupled to produce the power output 38. Additionally, the energy storageunit 26 may be adapted to utilize multiple energy storage devices inseries, for example, activating a new device when the previous device isnot longer charged.

In the illustrated embodiment, the charger 28 is shown located in thecaddy 20 and receiving primary power 41 from an external source.However, in other embodiments, the charger 28 may be located external tothe caddy 20. For example, in one embodiment, the energy storage device36 may be configured to be removed from the caddy 20 and placed in theexternally located charger 28 for charging before being replaced in theunit. During use, the charger 28 is configured to recharge the energystorage device(s) from a primary power source. For example, the energystorage devices may be recharged from a larger welder, grid power, andso forth.

During operation, the power conversion circuitry 30 is configured toreceive a power output from the energy storage device 36 and to convertthe received power output to an appropriate auxiliary power output 40.For example, the power conversion circuitry may be adapted to receive aDC power input and to convert the input to an AC power outputappropriate for use by auxiliary devices, such as lights and grinders.It should be noted that some embodiments of the caddy 20 may not includepower conversion circuitry 30 and may not output the auxiliary output40.

Still further, during operation, the controller 24 is configured tocontrol operation of the components of the caddy 20 to meet the poweroutput demand of the welder and to reduce or eliminate the possibilityof damage to the caddy and/or the welder. To that end, the controller 24includes control circuitry 32 coupled to memory 34. The controlcircuitry 32 may be configured to monitor the charge level of the energystorage device 36 and to recharge the energy storage device when thecharge level is low and a primary power source is available forcharging. Additionally, the control circuitry 32 may maintain the energystorage device 36 at a predetermined temperature and otherwise manageoperation of the energy storage device, as described in detail below. Tothat end, the control circuitry 32 may store parameters to the memory 34and retrieve such parameters during operation as necessary. For example,the memory 34 may include information regarding allowable charge levelfor the battery, allowable temperature levels for the battery, and soforth.

FIG. 3 is a block diagram illustrating an exemplary charging system 42for the energy storage device 36 in accordance with aspects of thepresent invention. The charging system 42 includes primary power 44, thecharger 28, the energy storage devices 36 and the welder 10. Thecharging system 42 illustrates exemplary ways in which the energystorage device may be charged during welding. For example, in oneembodiment, the primary power 44 may be supplied to the charger 28 androuted through the energy storage device, as indicated by arrow 46. Aportion of the incoming power may be dedicated to recharging the energystorage device 36 and another portion of the incoming power may berouted to the welder 10, as indicated by arrow 48, to meet the powerrequirements of the welding operation.

In another embodiment, the primary power 44 may be routed to the charger28, and power from the charger 46 may be split to provide the energystorage device 36 with charging power and to provide the welder withpower, as indicated by arrow 50. Still further, primary power 44 may berouted through the charger 28 and directly to the welder 10, asindicated by arrow 52, and a separate power output may be provided tothe energy storage device 36 from the charger 28, as indicated by arrow46. As such, the energy storage device 36 may be adapted to be chargedduring welding or when a weld is not occurring.

FIG. 4 illustrates an exemplary method 54 that may be employed by thecontroller 24 of FIG. 2 to manage operation of the energy storage device36 in an embodiment in which the energy storage device is a battery. Themethod 54 begins by monitoring the battery temperature (block 56). Sucha step may be of importance for the maintenance of the battery duringextreme weather (e.g., cold or warm temperatures) to maintain depletionrates of the battery within a predetermined range. The method 54 furtherincludes the step of implementing control to maintain the batterytemperature within a desired range (block 58). For example, apredetermined acceptable battery temperature may be maintained in thememory 34, and if the battery temperature exceeds such a range, theoperator may be alerted to a battery temperature error.

The method further includes monitoring the charge level of the battery(block 60) and implementing control to maintain the battery charge levelwithin a desired range (block 62). Here again, the memory 34 may storethe desired charge level ranges, and the control circuitry 32 maymonitor the charge level of the battery to ensure that the charge levelof the battery is maintained within the desired range. For example, ifthe battery charge level is depleted to a predetermined threshold level,the control circuitry may alert the operator that the battery needs tobe recharged soon.

Still further, the method 54 includes alerting the operator if batteryshutdown is imminent (block 64), activating an engine-driven welder tostart battery recharge (block 65) if possible, and shutting down thebattery output if a critical error is detected (block 66). For example,if primary power for recharging is not available and the battery chargelevel is depleted below a desired threshold, the controller may alertthe operator to the error and shut down battery output to substantiallyreduce or prevent the likelihood of damage to the battery and/or thewelder. For further example, if primary power (e.g., an engine-drivengenerator) is available for charging, the controller may commandactivation of the primary power source via a wired or wirelesscommunication device, thus starting the recharging of the battery.

While only certain features of the invention have been illustrated anddescribed herein, many modifications and changes will occur to thoseskilled in the art. It is, therefore, to be understood that the appendedclaims are intended to cover all such modifications and changes as fallwithin the true spirit of the invention.

1. A welding system, comprising: a welding power supply configured toprovide a power output for a welding operation; and an energy storagecaddy comprising at least one energy storage device, the caddy beingseparate from the welding power supply and adapted to couple to thewelding power supply, and being configured to provide a voltage outputto the welding power supply, wherein the welding power supply isconfigured to receive the voltage output and to convert the voltageoutput to the power output for the welding operation.
 2. The weldingsystem of claim 1, wherein the voltage output is a DC voltage outputbetween approximately 80V and approximately 500V.
 3. The welding systemof claim 1, wherein the energy storage caddy further comprises a chargerconfigured to receive primary power and to utilize the primary power tocharge the at least one energy storage device.
 4. The welding system ofclaim 1, wherein the energy storage caddy further comprises controlcircuitry coupled to the at least one energy storage device andconfigured to regulate the voltage output based on at least one of acharge level of the at least one energy storage device, a load demand atthe welding power supply, and a temperature of the at least one energystorage device.
 5. The welding system of claim 1, wherein the at leastone energy storage device comprises a battery.
 6. The welding system ofclaim 1, wherein the welding power supply is further configured to becoupled to a primary power source.
 7. The welding power supply of claim6, wherein the primary power source is a generator and the voltageoutput is configured to be coupled with a primary power output from thegenerator to provide the power output for the welding operation.
 8. Thewelding power supply of claim 6, further comprising a charger configuredto charge the at least one energy storage device with the primary powerfrom the primary power source.
 9. A retrofit kit for a welding system,comprising: an energy storage caddy configured to generate a poweroutput and to provide the generated power output to a welding powersupply, the energy storage caddy comprising: an energy storage deviceconfigured to discharge to produce the power output; and controlcircuitry coupled to the energy storage device and configured to controlthe power output based on at least one of a charge level of the energystorage device, a load demand at the welding power supply, and atemperature of the energy storage device.
 10. The retrofit kit of claim9, wherein the energy storage caddy further comprises a chargerconfigured to charge the energy storage device when the controlcircuitry detects a low charge level of the energy storage device. 11.The retrofit kit of claim 9, wherein the control circuitry is furtherconfigured to alert a user to the presence of an error when thetemperature of the energy storage device is not within a predeterminedrange and the charge level of the battery is not within a predeterminedrange.
 12. The retrofit kit of claim 9, wherein the control circuitry isfurther configured to command a generator via a wired or wirelesscommunication link to turn ON to provide alternating current (AC) powerto charge the energy storage device.
 13. The retrofit kit of claim 10,wherein the control circuitry is configured to control the charger tocharge the energy storage device when a welding operation is notoccurring.
 14. The retrofit kit of claim 9, wherein the energy storagedevices comprises at least one of a Li ion battery, a Ni-Mh battery, aNi—Cd battery, and a fuel cell.
 15. The retrofit kit of claim 9, whereinthe power output is a direct current (DC) power output, and the energystorage caddy further comprises power conversion circuitry configured toconvert the DC power output to an AC power output.
 16. The retrofit kitof claim 15, wherein the energy storage caddy is further configured toprovide the AC power output to one or more auxiliary devices.
 17. Anenergy storage caddy for a welding system, comprising: an energy storagedevice; and control circuitry configured to control the energy storagedevice to discharge to provide a direct current (DC) voltage output to awelding power supply, to monitor a charge level of the energy storagedevice, and to alert a user to an error when the charge level of theenergy storage device falls below a predetermined limit.
 18. The energystorage caddy of claim 17, wherein the DC voltage output is betweenapproximately 80V and approximately 500V.
 19. The energy storage caddyof claim 17, wherein the energy storage device is configured to beremoved from the energy storage caddy.
 20. The energy storage caddy ofclaim 17, configured to be coupled to a charger adapted to restorecharge to the energy storage device when the energy storage device isnot fully charged.
 21. The energy storage caddy of claim 17, furthercomprising power conversion circuitry configured to convert the DCvoltage output to an AC power output to power one or more auxiliarydevices.